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Suicidality is still an understudied problem in Bulgaria especially on a subnational (regional) level.
To collect data on suicidality in two major regions of Bulgaria with a population over 250,000 each (Plovdiv and Pleven) for a six years period (2009–2015).
To analyze demographic, health-related and other characteristics associated with suicidal behavior as well as motives and methods of suicide.
Data were extracted from relevant documentation (medical records, public health reports, etc.) and statistically processed upon collection.
Majority of suicide victims were males between 45 and 64 years while most suicide attempts occurred among 18–29 years old females.
Leading method of suicide was hanging, followed by jumping from high places and use of firearm.
Prevailing suicidal motives were psychotic symptoms, serious somatic illnesses and family problems. Depression accounted for 25% of all suicide cases and in another 25% motivation could not be identified because of insufficient data.
The proportion of unemployed among suicide committers was not significantly higher than that of employed and retired.
Severe mental disorders are a major trigger of suicidal behavior.
Personal relationships should be targeted by suicide prevention interventions.
Somatic illnesses are increasingly important suicide risk factor driven by the ongoing process of population aging.
Frontline healthcare professionals should be trained to explore underlying suicidal motives and actively probe for depression in each case of suicidal behavior.
Unemployment related suicide risk is most likely mediated through an adaptation crisis mechanism induced by the abrupt change of social status.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
GravityCam is a new concept of ground-based imaging instrument capable of delivering significantly sharper images from the ground than is normally possible without adaptive optics. Advances in optical and near-infrared imaging technologies allow images to be acquired at high speed without significant noise penalty. Aligning these images before they are combined can yield a 2.5–3-fold improvement in image resolution. By using arrays of such detectors, survey fields may be as wide as the telescope optics allows. Consequently, GravityCam enables both wide-field high-resolution imaging and high-speed photometry. We describe the instrument and detail its application to provide demographics of planets and satellites down to Lunar mass (or even below) across the Milky Way. GravityCam is also suited to improve the quality of weak shear studies of dark matter distribution in distant clusters of galaxies and multiwavelength follow-ups of background sources that are strongly lensed by galaxy clusters. The photometric data arising from an extensive microlensing survey will also be useful for asteroseismology studies, while GravityCam can be used to monitor fast multiwavelength flaring in accreting compact objects and promises to generate a unique data set on the population of the Kuiper belt and possibly the Oort cloud.
In this study, we investigate a concept that can be used to improve the magnetic field homogeneity in a microwave cavity applied in a novel, high-performance atomic frequency standard. We show that by modifying the boundary conditions in the case of a loop-gap geometry, a good improvement of the field homogeneity can be obtained. Such a design demonstrates high potential to improve the frequency stability; it is compact and hence suitable for a future generation of compact, high-precision frequency standards based on vapor cells and a pulsed optical pumping (POP) regime (POP atomic clocks).
We carried out a pivot experiment to select distant luminous late-type stars on the basis on their 2MASS and GLIMPSE photometry. Low-resolution infrared spectra enabled us to measure the equivalent widths (EWs) of their CO band-heads at 2.293 μm, and to confirm an extraordinarily high detection rate of red supergiants (RSGs), i.e. 61% (Messineo et al. (2016)).
We conducted infrared spectroscopic observations of bright stars in the direction of the molecular clouds W33 and GMC G23.3 − 0.3. We compared stellar spectro-photometric distances with parallactic distances to these regions, and we were able to assess the association of the detected massive stars with these molecular complexes. The spatial and temporal distributions of the detected stars enabled us to locate sources of ionizing radiation and to gather precise information on the star formation history of these clouds. The studied clouds present different distributions of massive stars.
This report summarizes epidemiological data on nephropathia epidemica (NE) in the Republic of Tatarstan, Russia. NE cases identified in the period 1997–2013 were investigated in parallel with the hantavirus antigen prevalence in small rodents in the study area. A total of 13 930 NE cases were documented in all but one district of Tatarstan, with most cases located in the central and southeastern districts. The NE annual incidence rate exhibited a cyclical pattern, with the highest numbers of cases being registered once in every 3–5 years. The numbers of NE cases rose gradually from July to November, with the highest morbidity in adult males. The highest annual disease incidence rate, 64·4 cases/100 000 population, was observed in 1997, with a total of 2431 NE cases registered. NE cases were mostly associated with visiting forests and agricultural activities. The analysis revealed that the bank vole Myodes glareolus not only comprises the majority of the small rodent communities in the region, but also consistently displays the highest hantavirus prevalence compared to other small rodent species.
A new method to determine the peak intensity of focused relativistic laser pulses is experimentally justified. It is based on the measurement of spectra of electrons, accelerated in the beam waist. The detected electrons were emitted from the plasma, generated by nonlinear ionization of low-density gases (helium, argon, and krypton) in the focal area of a laser beam with the peak intensity >1020 W/cm2. The measurements revealed generation of particles with the maximum energy of a few MeV, observed at a small angle relative to the beam axis. The results are supported by numerical particle-in-cell simulations of a laser–low-density plasma interaction. The peak intensity in the focal region derived from experimental data reaches the value of 2.5 × 1020 W/cm2.
AlGaN-based SQW heterostructures grown by plasma-assisted molecular beam epitaxy on c-Al2O3 substrates have been studied with high resolution transmission electron microscopy (HR TEM), photoluminescence spectroscopy and x-ray diffraction. The high-temperature (780°C) synthesis of the AlN buffer layer nucleated on c-Al2O3 by a migration enhanced epitaxy and including several ultra-thin GaN interlayers grown under moderate N-rich conditions was shown to be the optimum approach for lowering the threading dislocations density down to 108-109 cm-2. HR TEM study has confirmed the fine structure of single quantum wells (SQW) formed by a sub-monolayer digital alloying technique and revealed different kinds of compositional inhomogeneities in the AlxGa1-xN barrier layers of the heterostructures, including the formation of Al-rich barriers induced by the temperature-modulated epitaxy and the spontaneous compositional disordering along the growth axis for x=0.6-0.7. The influence of these phenomena on the parameters of the mid-UV stimulated emission observed in the SQW structures has been studied as well.
The Magellanic System represents one of the best places to study the formation and evolution of galaxies. Photometric surveys of various depths, areas and wavelengths have had a significant impact on our understanding of the system; however, a complete picture is still lacking. VMC (the VISTA near-infrared YJKs survey of the Magellanic System) will provide new data to derive the spatially resolved star formation history and to construct a three-dimensional map of the system. These data combined with those from other ongoing and planned surveys will give us an absolutely unique view of the system opening up the doors to truly new science!
More than 20000 observations of Near Earth asteroids and comets are collected and reduced in Pulkovo Observatory during last 10 years. For observations of these objects two robotic telescopes are used – ZA-320M (Cassegrain system, D = 320 mm, F = 3200 mm) at Pulkovo and MTM-500M (Maksutov – Cassegrain system, D = 500 mm, F = 4100 mm) at Kislovodsk mountain station. These telescopes perform CCD observations of objects up to 18.0 and 20.5 magnitude, correspondingly. The results of observations are regularly submitted to Minor Planet Center.
We examine the association of a venture capital (VC) firm’s reputation with the post-initial public offering (IPO) long-run performance of its portfolio firms. We find that VC reputation, measured by the past market share of VC-backed IPOs, has significant positive associations with long-run firm performance measures. While more reputable VCs initially select better-quality firms, more reputable VCs continue to be associated with superior long-run performance, even after controlling for VC selectivity. We find that more reputable VCs exhibit more active post-IPO involvement in the corporate governance of their portfolio firms, and this continued VC involvement positively influences post-IPO firm performance.
On 24 August 2008, an outbreak alert regarding cases of acute gastroenteritis in Podgorica triggered investigations to guide control measures. From 23 August to 7 September, 1699 cases were reported in Podgorica (population 136 000) and we estimated the total size of the outbreak to be 10 000–15 000 corresponding to an attack rate of ~10%. We conducted an age- and neighbourhood-matched case-control study, microbiologically analysed faecal and municipal water samples and assessed the water distribution system. All cases (83/83) and 90% (89/90) of controls drank unboiled chlorinated municipal water [matched odds ratio (mOR) 11·2, 95% confidence interval (CI), 1·6–∞]. Consumption of bottled water was inversely associated with illness (mOR 0·3, 95% CI 0·1–0·8). Analyses of faecal samples identified six norovirus genotypes (21/38 samples) and occasionally other viruses. Multiple defects in the water distribution system were noted. These results suggest that the outbreak was caused by faecally contaminated municipal water. It is unusual to have such a large outbreak in a European city especially when the municipal water supply is chlorinated. Therefore, it is important to establish effective multiple-barrier water-treatment systems whenever possible, but even with an established chlorinated supply, sustained vigilance is central to public health.
Electromagnetic wave propagation along the interface between a magnetoactive plasma and a metallic screen is investigated analytically and numerically. It is shown that the waves have a Rayleigh character: they are superpositions of two partial waves. It is concluded that electromagnetic waves propagate only at frequencies lower than min (ωp, ωc), where ωp is the plasma frequency and ωc is the cyclotron frequency. The field topology is found, and the physical character of the waves is discussed.
During 2001–2002 we investigated current contamination of soils in several places in the Chornobyl zone. We have measured the content of alpha emitting isotopes Pu, 241Am, 154,155Eu, 90Sr, and 137Cs in layers of soil up to the depth of 30 cm. By including the two mechanisms of migration: convection and diffusion in our model, we were able to estimate the ecological and effective half-lives of self-purification processes for these layers of soil. Effective half-lives vary from 20 to 400 years dependent upon the type of soil and the isotopes.
An electrochemical capacitive sensor with electrode separation in the order of the Electrical Double Layer width (Debye length) of the analyte solution is presented for extremely sensitive and label-free analysis of Nucleic Acids. As the Electrical Double Layers (EDL) from both the capacitive electrodes interact and overlap each other in the reduced space confinement, the contribution from the electrode polarization effects and noises due to bulk sample resistance are found to be minimized. The dielectric property changes during hybridization reaction were measured using 10-mer nucleotide sequences. A 30-45% change in relative permittivity (capacitance) was observed due to DNA hybridization at 10Hz.
High speed atomic force microscopy (AFM) holds the promise of investigating dynamic systems in real time with single molecule resolution. With the big push towards understanding more complex systems such as cell mechanics or cell-cell and cell-virus interactions, a tool is required that can extract information about these processes in real time in a physiological environment. Atomic force microscopy has been successfully used for investigations of many biological systems and materials in real life conditions, but taking AFM images takes too long to follow many biologically relevant processes. Therefore, attempts have been made to develop high speed AFM by reengineering all the components of an AFM system and much progress has been made. To be useful for investigations of biological systems however, it is often essential to keep imaging forces low in order to get good image quality and not to damage the sample. In this paper we will discuss new small AFM cantilevers we've developed to combine high resonance frequencies for faster imaging with low spring constants for gentle imaging.
Velo-cardio-facial syndrome (VCFS) is associated with interstitial deletions of chromosome 22q11. About 30% of patients with VCFS have psychosis, and the rate of these deletions in schizophrenia has been reported to be about 1%. Even higher rates of VCFS deletions have been reported for childhood-onset schizophrenia.
To test the hypothesis that there is an increased rate of VCFS among patients with early-onset psychosis (age at onset < 18 years). We screened 192 early-onset patients and 329 patients with adult-onset schizophrenia.
We genotyped the patients and 444 healthy controls for hemizygosity of five microsatellite markers and one single nucleotide polymorphism that map to the 22q11-deleted region.
One patient had a VCFS deletion, confirmed with semi-quantitative polymerase chain reaction. None of the controls showed a pattern of genotypes consistent with hemizygosity.
VCFS may be less frequent among patients with psychosis than previously suggested; this rate is not increased among early-onset patients.
In the present work, a novel method of synthesis has been developed to obtain highly dispersed oxide powders. This method is based on the combination of hydrothermal and ultrasonic treatment and uses the effect of acoustic cavitation.
Hydrothermal-ultrasonic treatment was carried out under the following conditions: T= 423 - 523 K, t = 10 min. -3 h. and ultrasonic frequency ν = 21.5 kHz. The control experiments (without ultrasound) were performed under the same conditions. The products were characterized by X-ray diffraction (XRD), thermal analysis (TGA), transmission electron microscopy (TEM). The specific surface area was determined by the BET method.
It was found that high-temperature hydrolysis of cobalt (II) nitrate in ultrasonic field results in formation of considerably smaller particles of Co3O4 in comparison with conventional high-temperatures hydrolysis (mean particle size decreases from 600–650 nm to 60–70 nm). It must be noted that Co3O4 samples obtained by hydrothermal-ultrasonic treatment possess mesoporous structure.
Ultrasonic-hydrothermal processing of amorphous gels of zirconyl and titanyl hydroxides leads to significant raise of the rate of crystallization process and formation of nanopowders of zirconia and titania (mean particle size 7–16 nm).
It must be pointed that the use of ultrasonic treatment during hydrothermal processing of amorphous gel of zirconyl hydroxide and 0.3 M aqueous solution of H2TiO(C2O4)2 leads to increase of the content of thermodynamically stable phases in the products of synthesis.
We have investigated the correlation between microstructure, DC resistivity and magnetoresistance of SrRuO3 thin films. The films were epitaxially grown by pulsed laser deposition on (001) SrTiO3 substrates in a temperature range of 690–810°C. According to x-ray measurements, the structure of all films is a mixture of highly oriented domains of strained orthorhombic phases (ortho-I and ortho-II) with different lattice parameters. Films deposited at 780°C show a minimum resistivity (270 μΩcm at 300 K) and a maximum magnetoresistance (8% at 5 K). These films consist mainly of ortho-I phase (a=0.393 nm). Films deposited at 690°C (predominantly ortho-II) have the highest resistivity (up to 1700 μΩcm at 300 K) and lowest magnetoresistance (3% at 5K).
We have been able to deduce a temperature dependence of the built-in potential in La2/3Sr1/3MnO3 grain boundary junctions. This has been performed by trimming a single grain boundary down to 1μm width with a focused ion-beam. We can thereby see the impact of single domain walls on the magnetoresistance and the current-voltage characteristics. We have also demonstrated the effect of averaging as we increased the number of junctions.